Lithographic damping-roller.



c. HENDERSON.

LITHOGRAPHIC DAMPING ROLLER.

APPLICATION FILED NOV. 29. I915.

Patented Oct. 8,

i I 506E501 drawings,

UNITED STATES PATENT OFFICE.

CARL HENDERSON, 01 OAK PARK, ILLINOIS, ASSIGNOR T0 MIEHLE PRINTING PRESS& MANUFACTURING COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OFILLINOIS.

LITHOGRAPHIC DAMPING-ROLLER.

Specification of Letters Patent.

Patented Oct. 8, 1918.

To all whom it may concern:

Be it known that I, CARL Hnnnnnson, a citizen of the United States,residin at Oak Park, in the county of Cook and tate of Illinois, haveinvented certain new and useful Improvements in LithographicDamping-Rollers, of which the following is a specification. y

In connection with lithographic printing presses, damping rollers are.used and it has been .usual to employ for this purpose a mandrel ofmetal or other non-yielding substance with a cylindrical covering offelt or other similar absorbent fabric by which the wateris taken up andtransferred. It is necessary that the surface speed of the roller shallcorrespond to that of the coacting cylinder and it is not uncommon forthe fabric covering of the rollers to creep .in spots, due to slightdifferences in surface speed, and thusform local protuberances orwrinkles which prevent perfect operation.

As it is exceedingly diflicult if not prac-.

tically impossible to secure and maintain absolute uniformity of surfacespeed, I have avoided the difficulties above pointed out by designing anabsorbent covering for the damping roller which provides for the necessary slippage and maintains a smooth surface at all times.

Inorder that the invention may be readily understood, preferred andmodified embodiments of the same are set forth in the accompanlyingdrawings. and in the following detai ed description based thereon. It w'1 be obvious, however, that the invention may be embod ed in othervaried and constructional forms, wherefore it is to be understoodthatfthe drawingand description are to be taken in an illustrative andnot .in an unnecessarily limiting sense. .In these Figure 1 is adiagrammatic view illustrating the damping mechanism of a press of thelithographic type; I

- Fig. 2' is a sideelevation of the dampg roller showing one endinlon'gitudinal section; I

Figs.- 3 and 4 arerespectively; sectional and elevational views-of anabsorbent disk forming one of the component parts of the rollers;

' I f Figs. 5 and 6 are similar views of a spacing metal disk or ringforming one of the component parts of the roller; and

a modification.

In Fig. 1 of the drawing is shown in a diagrammatic manner the watertrough 11, the water roller 12, the ductor roll 13, the distributingroll 14, and the damping roller 15 arranged in a train in the usualmanner to act upon the blanket cylinder 0 of a press. It :is with theformation of the damping rollers 15 that the present invention has todo.

The dampening roller comprises a mandrel 16 having arranged thereon aseries of yielding. absorbent disks 17 of felt or other similar materialsuitable for the purpose. Between the adjacent absorbent disks 17 andalternating therewith is arranged a series of hard, firm non-absorbentdisks 18 of slightly less exterior diameter than the absorbent disk 17.The disks 17 and 18 are in the form of .rings having an, interiordiameter corresponding to that ofthe exterior diameter of the mandrel 16so that they can be readily slipped upon the mandrel and will turnthereon. At each end of the, mandrel 16.are threaded nuts 19 by meansofwhich the series of disks maybe clamped axially together whilepermitting of angular slippage on the mandrel. The ease of slippage willbe controlled by the 5. Fig. 7 is a fragmentary sectional view of degreeto which the nuts 19 are pressed against the series of disks.

It will be observed that by reason of the difference in exteriordiameterof the disks 17 and 18, the former will project peripherallybeyond the latter, and when axial pressure is applied by means of thenuts 19 that portion of the disk 17 between the firm spacing disk 18will be so far compressed "that the peripheral portions of the disk 17will meet over the outer edges of the disks 18 and thereby bridge thespace between each of the adjacent absorbent disks 17 and producev anunbroken absorbent periphery for'the roller. This is clearly illustratedin the right hand, end of Fig. 2 of the draw ing. The extreme terminalspacing disk 18 1 of the series, adjacent the nut 19, act as,anti-friction members or washers permit-i ing of the angular slippage ofthe entire 0? senes of disks upon the mandrel independ-" shown embodythe important advantageous ently of the nuts 19., It will be clear, how-.1111g817l1616011, a series of ever, that Where theprovis'ion'ofslippage is not' desired, the nut 19 may be screwed home upon the seriesof disks sufliciently to prevent any angular slippage.

In Fig. 7 is shown a slight modification,

the essential difference being that upon the mandrel 16 is arranged asleeve 20 in such manner as to provide for angular. slippage thereon,the rings 17 and 18 being mounted upon this sleeve, and clamps thereonby means of the-nut 21. The disks l7 and 18' would be clamped by meansof the nut 21 upon the sleeves 20 with suflicient degree of pressure toprevent angular slippage upon the sleeve; .the requisite slippage upon te mandrel being between the sleeve 20 and the mandrel 16, the diskswould be indirectly under the control of the adjusting nut 19, as in theformer case. However, the degree of pressure exerted by the nut 19 tocontrol slippage would been;

tirely independent of the axial compression exerted upon the disks 17and 18 by the end clamp or nut 21. I 4

It will be noted that the two constructions feature that the moisture inthe roll is confined substantially to the periphery thereof,

the central portion being tightly compressed between the spacing diskWhile the peripheral portion is comparatively free from compresslon.Moreover, the roller is wlthout seam and is thus perfectly true andremains true in use. A further advantage is the fact that by reason ofthe provision for slippage the damping rollers may be posi-' tivelydriven instead of by friction only; I claim:

1. In a device of the character described a roll comprising a mandrel, aseries ofv L yielding absorbent rings rotatably. mounted on the mandrel,and-means to I clamp the series of rings together axially of the man- 2.In a device of the character described,

a roll comprising a mandrel, a series of yielding absorbent rings and ofinter osed relatively unyielding spacing rings 0 less diameterrotatably-mounted on the mandrel, and meansto clamp the series of ringstogether axially of the mandrel.

3. In a device of the-character described, a roll comprising a mandrel,a series of yielding absorbent rings and of interposed relativelyunyielding spacing rings'of less diameter rotatively mounted on themandrel, and

means to clamp the series of ringstogether' axially of the mandrel andto regulate the ease'of rotation or angular slippage on the mandrel. I

4. In a damping roller, the combination of a mandrel, a series ofyielding absorbent sp c rings of but slightly less diameter arrangedbetween adjacent yielding "rings, and nuts r a threaded on the ends ofthe mandrel to clamp the series of firm and yielding rings togetheraxially of the mandrel,,whereby to isolate the absorbent rings exceptatj'their edges and to cause the rejecting peripheries of the adjacentyi'e ding ring to meet to form an unbroken absorbent peripheral surface,the clamping action ofthe nuts be ing limited" to anextent to permit ofangue (liar 1slippage of the rings relative to the manre of a mandrel, aseries of yielding absorbent rings rotatable thereon, a series of 'firmspacing rings of lessdiameter arranged bei 5. In a" dampiiig roller, thecombination beyond the peripheries of the spacing rings tween adjacentyielding rings, and nuts threaded on the ends of the mandrel to clampthe series of firm and yielding rings cause the projecting peripheriesof the adjatogether axially ofthe mandrel, whereby to cent yieldingrings to meet beyond the 6. In a damping roller,-the-combination ofama'ndrel, a sleeve rotatable thereon, a series of yielding absorbentrings on the sleeve,"a series offirm spacing rings of less diameterarranged between ,the adjacent yieldingrings upon the sleeve, a nutthreaded on the end'of thes'leeve to clamp the series of firmandyielding rings together axially thereof, and a nut threaded, on themandreland engaging the end of the sleeve tocontrol the angular slippageof the sleeve on the mandrel. I

7. In a damping roller, the combination of a mandrel, a s eeve rotatablethereon, a

. series of -yielding absorbent rings on the sleeve, a series of firmspacing rings of less diameter arranged between the adjacent yieldingrings upon the sleeve, a nut threaded on the 'endof the sleeve to clampthe series. of firm and yielding rings together axially thereof, and anut threaded on the mandrel and engaging theend of-the sleeve to controlthe angular slippage-of the sleeve on the mandrel, the clamping-actionof the two nuts being independentone of the other. In witness whereof Ihave hereunto signed my name in the presence of two subscribingwitnesses. 1

' Y CARL HENDlEllRSON. Witnesses: r I O. I. MANSUR C. D. GIBBS.

